Pen



FIG. 1 is a lower perspective view of a pen showing my new design with the pen tip retracted inside the body of the pen;

FIG. 2 is an upper perspective view of the pen shown in FIG. 1 with the pen tip extended from the body of the pen;

FIG. 3 is a side elevation view of the pen shown in FIG. 1;

FIG. 4 is a top plan view thereof;

FIG. 5 is a bottom plan view thereof;

FIG. 6 is a side elevation view of the pen shown in FIG. 2;

FIG. 7 is a top plan view thereof; and,

FIG. 8 is a bottom plan view thereof.

The broken lines in FIG. 1 illustrate environmental matter and form no part of the claimed design. 

The ornamental design for a pen, as shown and described. 